Certain types of biological tissue stimulators, such as heart pacemakers, have a low duty cycle, and draw relatively little power over the course of some time frame, say, an hour. On the other hand, other biological stimulator types have a higher duty cycle, and may thus draw relatively higher power. Such higher power stimulators include, for example, a class of cochlear implants, as well as electrical stimulators for muscles and for nerves, such as in the case of stimulators for muscles which have their nerves inoperative because of trauma or degenerative illnesses, or, for nerves which may not be receiving normal synaptic input from the other ordinarily incoming other nerves, because of loss or disconnection (i.e., severing of those other nerves). For example, the spinal column nerves may be severed at some point, and the restoration of function below the cut area may be enabled with high-powered electric stimulators. These functions may include lower gastrointestinal (GI) function, urinary functions, sexual functions, and walking and limb movement functions, all of which may be served by functional electrical stimulators (FES) or other neuromuscular stimulators.
Today's primary battery sources tend to be of not high enough energy density, or if high enough energy density, too expensive and too large for any real use as a primary battery for any of the uses and systems above. Consequently, there is a real, unmet need for such systems, and such a power unit. A high amount of energy stored in a small space is a high energy density apparatus. Such an apparatus can potentially supply a high amount of energy per unit time (power) before it is exhausted. The current teaching of the art is away from this high energy density, relatively cheap, primary battery and systems which utilize it, and toward small, relatively low energy density, rechargeable batteries.